Chair.



Patented Dec. 9', [902.

J. E. GILSUN.

CHAIR.

(Applicaion med sept. 13,1900.)

(Nos-loda.)

l x l n m U-Qy/// UNITED VSTATES PATENT OFFICE.

JOHN E. GILSON, OF PORT WASHINGTON, -WISCONSIN, ASSIGNOR TO THE GILSON MANUFACTURING COMPANY, OF PORT WASHINGTON, WIS- CHAIR.

SPECIFICATION forming' part of Letterslatent No. 715,258, dated December 9, 1902- Application iled September 13, 1900. Serial No. 29,868. (No model.)

To a/ZZ whom t may concern:

Be it known that I, JOHN E. GILSON, a citizen of the United States, and a resident of Port IVashington, in the county of Ozaukee and State of Wisconsin, have invented certain new and useful Improvements in Chairs; and I do hereby declare that the following is a full, clear, and exact description thereof.

My invention has for its object to simplify and cheapen the manufacture of that class of chairs having vertically-adjustable supports for preferably pivotal seats; and it consists in certain peculiarities of construction and combination of parts constituting a portion of the metal work for such chairs, as hereinafter particularly set forth with reference to the accompanying drawings and subsequently claimed.

Figure l of the drawings represents what is for the most part a vertical transverse section view of a construction and arrangement of parts embodied in my invention; Fig. 2, a plan view of the same, partly broken and in horizontal section; Fig. 3, an elevation of the assemblage, partly in vertical transverse section; and Fig. 4t, a detail sectional View of a portion of the base-casting element of said assemblage, a combined spindleguide and nut-guard bracket being shown in 'elevation on said casting.

Referring byletter to the drawings, A indicates a smooth-bore chair-base casting engaged by a screw-spindle B, that also engages a nut C, that bears against said casting. The spindle is shown as having its upper end provided with a socket for a cone-pointed pivot D, to which the standard for a chair-spider is rigidly connected, a fragment E of such a standard being herein illustrated. An annular groove b in the pivot D is engaged by ascrew F, that turns in the head of spindle B; but other means may be utilized to prevent separation of said pivot and spindle when a chair embodying the same is lifted. The otherwise cylindrical spindle has atleast one dat face that interrupts the continuity of the screw-thread thereon, and owing to the fact that said spindle can be most economically produced by casting it is herein shown as having two suc/h faces, one opposite the other, the parting of the mold for said spindle being along said faces. The' spindle being cast, its screw-thread ridges are milled to smooth the same, and any roughness found on the at faces of said spindle may be removed by grinding or otherwise, as found most economical and convenient.

The upper end of the base-casting is recessed to provide a radial seat for a tongue c of a cast-metal bracket G, that is held on said casting by a screw H, this tongue being flush with the aforesaid casting and extended into the bore of the same to oppose a iiat face of spindle B, and thus prevent rotation of said spindle without interfering with its 1ongitudinal movement up or down when the nut O is rotated in one direction or the other.

The lower endof the nut O is provided with a flange d, and a guard e, constituting part of bracket G, overlaps the ange to prevent said nut and the spindle engaged therewith from being lifted away from the aforesaid base-casting. To facilitate its manipulation, the nut is provided with a band-wheel ange f, as herein shown, and it may be made with a guard-engaging annular groove instead of the ange d, above specified.

Having thus described my invention, Vwhat I claim as new, and desire to secure by Letters Patent, is-

A smooth-bore chair-base casting provided at one end with a radial end recess open to the bore, a screw-spindle in the base-casting provided with'a longitudinal guideway, an adjusting-nut on the spindle, and a detachable nut-guard bracket having a spindleguide tongue held in the base-casting recess.

In testimony that I claim the foregoing I have hereunto set my hand, at Port 'Washington, in the county of Ozaukee and State of Wisconsin, in the presence of two witnesses.

C. A. SEIEERT, H. W. BoLENs. 

